Solid-Solid Extraction SSE, Application of SPE to AgSF

Extraction

Agar-supported fermentation (Ag-SF), a variant of solid-state fermentation (SSF), has recently been improved by the development of a dedicated 2m2 scale pilot facility, Platotex. We investigated the application of solid-phase extraction SPE to Ag-SF in order to increase yields and minimize the contamination of the extracts with medium constituents. The mycelium that requires oxygen to grow migrates to the top layer and forms a thick biofilm. The resin beads intercalate between the agar surface and the mycelium layer and directly trap the compounds secreted by the mycelium through a ‘solid-solid extraction’ process (SSE). The resin/mycelium layer is easily recovered by scraping the surface and the target metabolites extracted by methanol. Ag-SF associated to SSE represents an ideal compromise for the production of bioactive secondary metabolites with limited economic and environmental impact.